Fixed windows warning in MemoryMappedFileImpl.cc

src/ACGL/Utils/MemoryMappedFileWinImpl.cc

@@ -21,6 +21,7 @@ MemoryMappedFileWinImpl::MemoryMappedFileWinImpl(
     DWORD fileAccess = 0;
     DWORD fileShare = 0;
     DWORD fileSize = 0;
+	(void)fileSize;
     DWORD offsetLow = 0;
     DWORD offsetHigh = 0;